Solution‐Processable Transparent Organic Molecular Nanoadhesives for Exceptionally Durable Nanowire Electrodes

• Published in: Advanced electronic materials Vol. 6; no. 6
• Main Authors: Bok, Shingyu, Ahn, Kwangguk, Oh, Hwisu, Kwon, Nayoung, Lee, Jung Heon, Nam, Jaewook, Lim, Byungkwon
• Format: Journal Article
• Language: English
• Published: 01.06.2020
• Subjects: molecular nanoadhesives; silver nanowires; thin‐film heaters; touch panels; transparent electrodes
• ISSN: 2199-160X; 2199-160X
• DOI: 10.1002/aelm.201901440

Silver (Ag) nanowires (NWs) are promising building blocks for fabrication of flexible transparent electrodes, but their poor adhesion to polymeric substrates causes delamination of NWs from a substrate during repeated deformation, which leads to degradation in electrical performance. A new and simple approach is developed to dramatically improve mechanical, chemical, and thermal stability of a Ag NW electrode by hybridizing a NW network film with an organic molecular nanoadhesive layer without sacrificing its inherent excellent optoelectrical properties. It is discovered that some of pyridine derivatives such as 4‐dimethylaminopyridine can be solution‐processed and annealed to form a transparent layer with high adhesion to polymeric substrates such as poly(ethylene terephthalate). In addition to high optical transparency and electrical conductivity, the NW‐nanoadhesive hybrid film exhibits low surface roughness, reduced optical haze, and excellent adhesion to the substrate without delamination against 100 cycles of tape detachment and 10 000 cycles of bending tests at 1 mm of bending radius. Furthermore, the hybrid film exhibits good air‐oxidation and thermal stability over 24 h at 100 °C. The hybrid electrodes show good performance in applications for flexible touch panel and thin film heater. A highly adhesive, mechanically robust, and thermally stable Ag nanowire (NW)/organic nanoadhesive hybrid electrode is fabricated by simple solution coating and annealing process. The hybrid electrode exhibits high optical transparency and electrical conductivity as well as low surface roughness. Highly durable flexible touch panel and thin film heater are demonstrated using Ag NW/organic nanoadhesive hybrid electrode.